Advanced Man-Portable Air Defense Systems (MANPADS) present a significant threat to fixed-wing aircraft and helicopters. Mid-infrared laser-based infrared countermeasures (IRCM) systems could provide the needed protection from MANPADS for many types of aircraft. Unfortunately, with the complex pointer/tracker-turret assembly, these systems typically cost more than $1.5 million. This prohibitively high cost precludes use with large numbers of aircraft, leaving them unprotected from advanced MANPADS.
Laser beams can be pointed using a number of methods and mechanisms, some which allow aligning the laser beam with a sensor-determined direction, which is useful for IRCM. Among these are methods using turrets and/or one or more gimbaled mirrors, for example U.S. Pat. No. 6,020,955 “System for pseudo on-gimbal, automatic line-of-sight alignment and stabilization of off-gimbal electro-optical passive and active sensors” issued Feb. 1, 2000 to Peter Messina, and which is incorporated herein by reference. Messina describes an optical apparatus for use in auto-aligning line-of-sight optical paths of at least one sensor and a laser, comprising: at least one reference source for outputting at least one reference beam that is optically aligned with the line-of-sight of the at least one sensor, a laser reference source for outputting a laser reference beam that is optically aligned with the line-of-sight of the laser, a laser alignment mirror for adjusting the alignment of the line of sight of the laser beam, a sensor alignment mirror for adjusting the alignment of the at least one sensor, combining optics for coupling the plurality of reference beams along a common optical path, gimbal apparatus, a detector disposed on the gimbal apparatus for detecting the plurality of reference beams, a fine stabilization mirror disposed on the gimbal apparatus for adjusting the line of sight of the optical paths of the at least one sensor and the laser, and a processor coupled to the detector, the laser alignment mirror, the sensor alignment mirror, and the fine stabilization mirror for processing signals detected by the detector and outputting control signals to the respective mirrors to align the line-of-sight optical paths of the sensor and the laser. Other such systems or components are described in U.S. Pat. No. 6,288,381 issued Sep. 11, 2001 to Peter Messina titled “Integrated system for line-of-sight stabilization and auto-alignment of off-gimbal passive and active electro-optical sensors”, U.S. Pat. No. 6,878,923 issued Apr. 12, 2005 to Carlos Casteleiro titled “Low profile optical imaging system having a wide field of regard”, and U.S. Pat. No. 6,879,447 issued Apr. 12, 2005 to Carlos Casteleiro titled “Optical gimbal apparatus” which are all incorporated herein by reference. Such systems are complex and expensive.
U.S. Pat. No. 6,873,893 issued Mar. 29, 2005 to Sanghera et al. titled “Missile warning and protection system for aircraft platforms”, and U.S. Pat. No. 6,813,296 issued Nov. 2, 2004 to Goyal et al. titled “GASB-clad mid-infrared semiconductor laser”, which are incorporated herein by reference, describe other components that are used in some embodiments of the present invention.
There is a need for a low-cost laser pointer system that is much less complex than a conventional pointer/tracker-turret assembly.